EVSE Embedded Submetering & Communication Kenneth Brown, Leviton Manufacturing

Who is NEMA? NEMA is the association of electrical equipment and medical imaging manufacturers, founded in 1926 and headquartered in Arlington, Virginia. 400-plus member companies Manufacture diverse set of products power transmission and distribution equipment, lighting systems, factory automation and control systems, and medical diagnostic imaging systems. The U.S. electroindustry accounts for more than 7,000 manufacturing facilities, nearly 400,000 workers, and over $100 billion in total U.S. shipments.

Electric Vehicle Supply Equipment (EVSE) Section NEMA Electric Vehicle Supply Equipment/Systems Section represents manufacturers of products or assemblies installed for the purpose of safely delivering and managing electrical energy between an electric vehicle and an electrical source. Purpose: Market Development Education Technology, application, and product standards

EVSE Section Members

Key Drivers of Submetering To enable separate EV charging rates National Conference on Weights and Measures (NCWM) NIST Method of Sale Regulation for retail sale of electricity as vehicle fuel (publicly accessible) To enable power monitoring for non-commerce applications

Purpose of the Guide for Embedded Metering and Communication The purpose is to provide guidance for EVSE’s that include a metering function The EVSE incorporates a communication protocol access to metering data Where codes, standards and regulatory documents relative to EVSE metering exist, the guide will harmonize with those standards The guide will develop standards where requirements do not already exist

The Scope North American types of EVSE embedded meters used in commerce and non-commerce applications The guide addresses different capabilities, installations and certifications Tiered functionality for embedded meters including tamper resistance, accuracy, calibration, communication, security, and reliability AC and DC charging EVSEs

Key Issues for the Guide Commerce versus Non-Commerce EVSE requirements: Accuracy Requirements – acceptance of proposed requirements by NIST and utilities for billing Distinction of requirements for Embedded EVSE versus separate submeters Metering configuration options for an EVSE 

National Conference on Weights and Measures Professional nonprofit association of state and local weights and measures officials, federal agencies, manufacturers, retailers and consumers From fuel pumps to toilet paper Goal: uniformity in W&M laws and regulations among states and local jurisdictions to facilitate trade, fair competition, consumer protection NIST is NCWM partner and maintains relevant Handbooks

Method of Sale Regulation Handbook 130 governs method of sale Requires retail sale of electricity as vehicle fuel to be done by energy measure (kWh, MJ) Metering required

National Conference on Weights and Measures Handbook 44 governs technical requirements for measuring Provisional Key Agreements Targets EVSE embedded metering only. A “submeter” document may be needed later Accuracy defined and tested at coupler. Compares calibrated tester reading with display indication. Little or no ANSI C12 requirements would apply

National Conference on Weights and Measures Handbook 44 Provisional Key Agreements (cont.) Tamper proof: seal and audit trail for metrological components No printers, coin operations, field calibration Energy units: kWh only Billing: kWh and/or time Billing & Audit Information available electronically

NEMA Standards Activities Monitoring consumer EV charging habits is direct monitoring of charge time & power consumption The cost of an embedded meter is low relative to the infrastructure costs required to add a separate submeter The EVSE can send meter data to a remote location for storage and developing billing information EV users will know what they’re paying to charge their vehicles

NEMA Standards Activities NEMA is developing a guide to identify existing requirements and provide recommendations for embedded metering The guide recommends a tiered functional approach for embedded meters including tamper resistance, accuracy, calibration, communication, security and reliability. The guide will recommend accuracy, test and calibration requirements for the EVSE embedded metering Key performance standards related to embedded EVSE include: UL 2231 & 2594, SAE J1772, and ANCI C12

NEMA Standards Activities (cont’d) The new “Guide for EVSE Embedded Metering and Communication” encompasses the North American types of meters emerging within EVSEs The stakeholders expected to benefit from the new Guide are EVSE manufacturers, utilities, automakers, smart meter manufacturers, EV drivers, EVSE owners, and regulators The guide will describe methods of test and determining accuracy of commercial EVSEs with embedded meters by measuring the performance at the charge connector The working group has identified gaps in existing standards and is working diligently to close the gaps through development of new processes and procedures

Commerce EVSE Embedded Metering System LAN Charging provider Utility EVSE with Meter Provider billing. Utility demand response requests. V2G requests Customer Billing Energy Communications NEMA EVSE Embedded Metering Scope

Non-Commerce EVSE Embedded Metering Total energy usage, EV energy usage data, DR, VTG requests MM LAN Utility web site Utility energy use monitoring EVSE with Meter Billing to customer = Total energy used – rate discount for EV usage. Energy Communications NEMA EVSE Embedded Metering Scope

Questions? Thank You! Kenneth Brown, Leviton Manufacturing kbrown@leviton.com